Improvement in screw-cutting die-chucks



J; G. & G. J. BORN.

SCREW CUTTING DIE-CHUCKS.

No. Patented. July-11,1876

WITNESSES NJEIERS. FnoTb-u'moeamnm, WASHINGTON. o. c.

UNITED STATES PATENT QFFIC'E.

JOHN G. BORNAND GEORGE J. BORN, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN SCREW-CUTTING DlE-CHUCKS.

Specification forming part of Letters Patent No. 179,677, dated July 11,1876; application filed June 6, 1876.

To all whom it may concern:

Be it known that we, JOHN G. BORN and GEORGE J. BORN, of Pittsburg, inthe county of Allegheny and State of Pennsylvania, have invented a newand Improved Die-Chuck, of which the following is a specification Theinvention consists of the two parts of a divided screw cutting die,fixed on slides, which are fitted in a supporting-plate and combinedwith an eccentric and shaft in such manner that the die is opened andclosed readily by the eccentric.

Figure l is an elevation of our improved diechuck. Fig. 2 is a sectionon the lineyy; and Fig. 3 is a section on the line 00 41:.

Similar letters of reference indicate correspondin g parts.

A represents a supporting plate or stock, in which the plate B, havingone-halt'of the die 0, is fitted in dovetail or equivalent grooves toslide forward and backward a little. D is another plate, having part Eof the die attached to it, and being fitted to slide in plate B. F is aneccentric on shaft Gr, fitted in bearings at I in plate B, and alsoextended through elongated bearings J in the supporting-plate A, inwhich it is free. to move to allow plateB to be adjusted to the holeK inthe supportingplate for the rod or tube to be screw threaded. The shaftG is fitted at K for .the application of a crank for turning it to openand close the die, which it accomplishes by pushing against plate D at Land M. N is a groove cut in the plate B, under the meeting point of thedies, to allow the chips to fall out so as not to clog between the dies,and the opening between the dies is made a little wider at the lowerside for the same purpose. Bis a stop-screw for preventing the plate Dfrom sliding too far either way.

Having thus described our invention, we claim as new and desire tosecure by Letters Patentt The combination of the independently-slidingdie-plates B and D, supporting-plate A, shaft G, and eccentric F,substantially as specified.

JOHN G. BORN.

/ GEORGE J. BORN.

Witnesses:

JNo. H. FRIDAY, ALEX. SEANOR.

